JP2010190539A - Refrigerant-to-refrigerant heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refrigerant-to-refrigerant heat exchanger maximizing a heat transfer area, improving strength of an inner pipe, and preventing vibration and noise. <P>SOLUTION: This refrigerant-to-refrigerant heat exchanger 4 includes a cylindrical outer pipe 10 having a high-temperature refrigerant inflow pipe 45a projected at one side end of an outer peripheral face, and a high-temperature refrigerant outflow pipe 14b projected at the other side end, the plurality of inner pipes 12 disposed in a state of penetrating through the outer pipe 10, and a central pipe 13 coaxial with the outer pipe 10, and disposed in a state of being joined to outer peripheral faces of the inner pipes 12, and the outer peripheral faces of the inner pipes 12 and an inner peripheral face of the outer pipe 10 are separated by a prescribed distance. The strength of the inner pipe 12 is improved by the central pipe 13, and its heat transfer area is further enlarged. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an inter-refrigerant heat exchanger that performs heat exchange between refrigerants, and more particularly to a configuration that improves heat exchange efficiency.

  A conventional inter-refrigerant heat exchanger, for example, as shown in Patent Document 1, stores a pair of small-diameter high-pressure refrigerant pipes in a large-diameter low-pressure refrigerant pipe so that a pair of high-pressure refrigerant and low-pressure refrigerant is contained. A liquid gas heat exchanger is configured as an inter-refrigerant heat exchanger that performs heat exchange. The heat pump unit of the heat pump hot water supply device is composed of a compressor, a gas cooler, an expansion valve that is a decompression mechanism, and an evaporator in sequence to form a refrigerant circuit, and a high-pressure refrigerant that is supplied from the gas cooler to the expansion valve and a compressor that compresses The liquid gas heat exchanger described above is provided so as to perform heat exchange between refrigerants between the low-pressure refrigerants supplied to the machine.

  However, by storing a pair of small-diameter high-pressure refrigerant pipes in a large-diameter low-pressure refrigerant pipe in a pair, there is a risk that the high-pressure refrigerant pipe will be affected by the liquid refrigerant flowing around it and generate vibration and noise. In addition, the heat transfer area from the gaseous refrigerant flowing in the high-pressure side refrigerant pipe to the liquid refrigerant flowing in the low-pressure side refrigerant pipe is limited to the pipe surface area of the high-pressure side refrigerant pipe, which can improve the heat transfer efficiency. It was desired.

JP 2008-224073 (page 7, FIG. 1)

  In view of the above problems, the present invention expands the heat transfer area for heat exchange as much as possible and improves the strength of a small-diameter pipe arranged in a large-diameter pipe to suppress vibration and noise. It aims at providing the heat exchanger between refrigerant | coolants which can be performed.

  To solve the above problems, the present invention provides a refrigerant inflow pipe at one end, a refrigerant outflow pipe at the other end, and an outer pipe for circulating the refrigerant flowing from the refrigerant inflow pipe to the refrigerant outflow pipe; A plurality of inner pipes that are provided in the outer pipe and circulate a refrigerant that exchanges heat with the refrigerant that flows in the outer pipe and a central pipe through which the refrigerant in the outer pipe flows, and the outer peripheral surface of the inner pipe and the While being spaced apart from the inner peripheral surface with the outer tube, the outer peripheral surface of the plurality of inner tubes and the outer peripheral surface of the central tube are joined.

  Further, the compressor, the heat source side heat exchanger, the inter-refrigerant heat exchanger, the main decompression means, and the use side heat exchanger are sequentially connected, and the inter-refrigerant heat exchanger and the main decompression means In the refrigerant circuit formed by providing a bypass pipe branched from the passage, passing the bypass pipe through the inter-refrigerant heat exchanger via a sub-pressure reduction means, and connecting to the suction side of the compressor, the inter-refrigerant heat exchanger However, an outer pipe having a refrigerant inflow pipe at one end and a refrigerant outflow pipe at the other end, and a plurality of inner pipes provided in the outer pipe and spaced apart from the inner peripheral surface of the outer pipe. It consists of a central tube joined to the outer peripheral surface of the inner tube and through which the refrigerant in the outer tube flows. The high-temperature refrigerant flowing out from the outdoor heat exchanger and flowing into the main decompression means flows through the outer tube. On the other hand, the bar that flows out from the sub-pressure reducing means to the inner pipe and flows out to the suction side of the compressor. It has a configuration comprising by circulating a coolant path tube.

  According to the first aspect of the present invention, the outer peripheral surface of the plurality of inner pipes and the outer peripheral surface of the central pipe are joined, so that the strength of the inner pipe can be improved and the generation of vibration and noise can be prevented. It has become.

  According to the invention described in claim 2, since the high-temperature refrigerant flowing in the outer pipe dissipates heat to the refrigerant flowing in the inner pipe and the outside air, the refrigerant flowing out of the outdoor heat exchanger and flowing into the main decompression means is efficiently used. It can be cooled down.

It is a refrigerant circuit as an example using the heat exchanger between refrigerants by the present invention. It is sectional drawing and principal part sectional drawing of the heat exchanger between refrigerant | coolants by this invention.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail as examples based on the attached drawings.

  As a refrigerant circuit using the inter-refrigerant heat exchanger according to the present invention, for example, a refrigerant circuit 1 shown in FIG. 1 includes a compressor 2, an outdoor heat exchanger 3, an inter-refrigerant heat exchanger 4, and a main expansion valve 5. The indoor heat exchanger 6 is sequentially connected by a pipe 8, and a bypass pipe 9 including a sub expansion valve 7 is branched from between the inter-refrigerant heat exchanger 4 and the main expansion valve 5. The bypass pipe 9 passes through the sub-expansion valve 7, passes through the inter-refrigerant heat exchanger 4, and is connected between the compressor 2 on the suction side of the compressor 2 and the indoor heat exchanger 6.

  The refrigerant that has been compressed by the compressor 2 to become high temperature and high pressure flows into the outdoor heat exchanger 3, and dissipates heat to the air flowing around the outdoor heat exchanger 3 to condense. The condensed refrigerant is cooled in the inter-refrigerant heat exchanger 4 by the refrigerant flowing through the bypass pipe 9 as described later, and becomes a supercooled state, and is depressurized by the main expansion valve 5 to become a low-temperature and low-pressure refrigerant. The low-temperature and low-pressure refrigerant flows into the indoor heat exchanger 6, absorbs heat from the air flowing around the indoor heat exchanger 6 and evaporates, and the evaporated refrigerant returns to the compressor 2. .

  The refrigerant branched from the inter-refrigerant heat exchanger 4 to the bypass pipe 9 is depressurized by the sub-expansion valve 7, becomes low temperature and low pressure, flows into the inter-refrigerant heat exchanger 4, and exchanges heat with the condensed refrigerant flowing from the pipe 8. Then, it recirculates to the suction side of the compressor 2. The refrigerant having exchanged heat with the refrigerant flowing in the bypass pipe 9 by the inter-refrigerant heat exchanger 4 is decompressed by the main expansion valve 5 and then flows into the indoor heat exchanger 6.

  Next, the above-described refrigerant heat exchanger 4 will be described. The inter-refrigerant heat exchanger 4 is disposed so as to penetrate the cylindrical outer tube 10 and the outer tube 10 as shown in the cross-sectional view of FIG. 2A and the main-part cross-sectional view of FIG. A plurality of inner pipes 12 and a central pipe 13 that is coaxial with the outer pipe 10 and that is disposed so as to be joined to the outer peripheral surface of the inner pipe 12. By joining the outer peripheral surface of the inner tube 12 and the outer peripheral surface of the central tube 13, it is possible to improve the strength of the plurality of spaced apart inner tubes 12, and the high-pressure refrigerant flowing in the outer tube 10 In addition to the vibration in the inner tube 12, the generation of noise caused by this can be prevented as much as possible.

  The outer pipe 10 has a high-temperature refrigerant inflow pipe 14a projecting from one end of the outer peripheral surface and a high-temperature refrigerant outflow pipe 14b projecting from the other end. For example, in the refrigerant circuit 1, one end of a pipe 8 connected to the outdoor heat exchanger 3 is connected to the high-temperature refrigerant inflow pipe 14a, and one end of the pipe 8 connected to the main expansion valve 5 is connected to the high-temperature refrigerant outflow pipe 15b. The refrigerant condensed by radiating heat in the outdoor heat exchanger 3 flows into the outer pipe 10 from the high-temperature refrigerant inflow pipe 14a and is heat-exchanged in the outer pipe 10, and then the high-temperature refrigerant outflow pipe It flows out of 14b and goes to the main expansion valve 5.

  The inner pipe 12 through which the low-temperature refrigerant flows is made of a copper material or a copper alloy having high thermal conductivity, and as shown in FIG. 2 (B), three inner pipes 12 are arranged so as to be even on the circumference in the outer pipe 10. In addition, the outer peripheral surface of the inner tube 12 and the inner peripheral surface of the outer tube 10 are separated by a predetermined distance. One end of the inner pipe 12 is connected to one side of a header 11a formed in a semiconical shape, and one end of a bypass pipe 9 connected to the sub-expansion valve 7 is connected to the other side of the header 11a. . The other end of the inner pipe 12 is connected to one side of a header 11b similarly formed in a semiconical shape, and a bypass pipe 9 connected to the suction side of the compressor 2 is connected to the other side of the header 11b. One end is connected.

  The refrigerant that has flowed into the bypass pipe 9 and has become low temperature and low pressure by the sub-expansion valve 7 flows into the header 11a and is diffused in the header 11a to be agitated to a uniform temperature. The refrigerant having a uniform temperature flows into the three inner pipes 12 and circulates them to exchange heat with the high-temperature refrigerant flowing in the outer pipe 10 to cool the high-temperature refrigerant, and then to the header 11b. It comes to leak. The refrigerant that has flowed out of the header 11b is returned to the suction side of the compressor 2 through the pipe 9.

  As described above, inside the three inner pipes 12, a central pipe 13 made of a copper material or a copper alloy having a high thermal conductivity and having a large diameter is disposed similarly to the inner pipe 12. The outer peripheral surface of 13 and the outer peripheral surface of the inner tube 12 are bonded together, and a bonding material 15 having high thermal conductivity is embedded in the gap around the bonded portion. The joint material 15 joins the outer peripheral surfaces of the inner tube 12 and the central tube 13 and increases the heat transfer area.

  By joining the tube walls of the three inner tubes 12 and the tube wall of the central tube 13 having a larger diameter than these, the heat transfer area due to the surface area of the inner tube 12 is increased. Heat transfer area due to surface area is added, and heat transfer area can be expanded. Further, since the bonding material 15 having high thermal conductivity is embedded in the gap around the joint portion between the inner tube 12 and the central tube 13, the heat from the inner tube 12 is efficiently transmitted to the central tube 13. It has become.

  The low-temperature refrigerant flowing through the inner pipe 12 exchanges heat with the high-temperature refrigerant flowing through the outer peripheral portion of the inner pipe 12 and the pipe surface of the central pipe 13 to cool the high-temperature refrigerant. At the same time, the refrigerant flowing inside the central tube 13 is also cooled, so that efficient heat exchange is performed.

  In addition, the outer peripheral surface of the inner tube 12 and the inner peripheral surface of the outer tube 10 are not in close contact with each other and are separated from each other so as to prevent heat from entering the inner tube 12 from the tube wall of the outer tube 10 as much as possible. Thus, disturbance due to heat intrusion or the like is suppressed, and the amount of heat exchange between refrigerants preset in the inter-refrigerant heat exchanger 4 can be sufficiently performed. Further, by flowing a low-temperature refrigerant through the inner tube 12 and flowing a high-temperature refrigerant through the outer tube 10, heat is efficiently transferred from the outer tube 10 covering the inner tube 12, and the heat exchange efficiency is improved. ing.

  Further, in order to improve the heat transfer efficiency from the refrigerant flowing in the outer pipe 10 to the refrigerant flowing in the inner pipe 12, the surface shape of the inner pipe 12 may be changed so that the contact area with the refrigerant increases. Although it is conceivable, according to the present invention, the outer peripheral surface or the inner peripheral surface of the single central tube 13 can be changed only by changing the outer peripheral surface or the inner peripheral surface of the single central tube 13 without providing the plurality of inner tubes 12 with a spiral shape or groove shape that increases the cost. Heat exchange capability can be improved between the refrigerant flowing through the pipe 10 and the refrigerant flowing through the inner pipe 12. In addition, by flowing a high-temperature refrigerant through the outer tube 10, heat can be radiated from the high-temperature refrigerant to the outside of the outer tube 10.

DESCRIPTION OF SYMBOLS 1 Refrigerant circuit 2 Compressor 3 Outdoor heat exchanger 4 Refrigerant heat exchanger 5 Main expansion valve 6 Indoor heat exchanger 7 Sub expansion valve 8 Pipe 9 Bypass pipe 10 Outer pipe 11a, 11b Header 12 Inner pipe 13 Central pipe 14a High temperature Refrigerant inflow pipe 14b High temperature refrigerant outflow pipe 15

Claims (2)

A refrigerant inflow pipe is provided at one end, a refrigerant outflow pipe is provided at the other end, an outer pipe that circulates the refrigerant flowing from the refrigerant inflow pipe to the refrigerant outflow pipe, and the outer pipe is provided in the outer pipe. A plurality of inner pipes that circulate a refrigerant that exchanges heat with the refrigerant that flows through and a central pipe through which the refrigerant in the outer pipe circulates,
The outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube are separated from each other, and the outer peripheral surface of the plurality of inner tubes and the outer peripheral surface of the central tube are joined together. Heat exchanger. A compressor, a heat source side heat exchanger, an inter-refrigerant heat exchanger, a main decompression unit, and a use-side heat exchanger are sequentially connected, and between the inter-refrigerant heat exchanger and the main decompression unit. In the refrigerant circuit formed by providing a branched bypass pipe, allowing the bypass pipe to pass through the inter-refrigerant heat exchanger via a sub-decompression unit, and connecting to the suction side of the compressor,
The inter-refrigerant heat exchanger is provided in the outer pipe with the refrigerant inflow pipe provided at one end and the refrigerant outflow pipe at the other end, and is separated from the inner peripheral surface of the outer pipe. A plurality of inner pipes and a central pipe that is joined to the outer peripheral surface of the inner pipe and through which the refrigerant in the outer pipe flows,
A high-temperature refrigerant flowing out from the outdoor heat exchanger and flowing into the main pressure reducing means flows through the outer pipe, while flowing out from the auxiliary pressure reducing means into the inner pipe and flows out to the suction side of the compressor A refrigerant circuit in which the refrigerant in the bypass pipe is circulated.

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